Before you can run FreeBSD, you need to start it up. That’s normally pretty straightforward: you turn the machine on, a lot of things scroll off the screen, and about a minute later you have a login: prompt or an X login window on the screen. Sometimes, though, the process is of more interest. You have a number of options when booting, and it’s also a source of a number of problems, so it pays to understand it. In this chapter we’ll look at the following topics: | 2 April 2003 17 00 47 The Complete FreeBSD page 523 In this chapter Starting the system Things you can do before booting What are you going to boot Running the kernel Single-user mode Shutting down and rebooting the system FreeBSD without disks Network booting Disk substitutes Starting and stopping the system Before you can run FreeBSD you need to start it up. That s normally pretty straightforward you turn the machine on a lot of things scroll off the screen and about a minute later you have a login prompt or an X login window on the screen. Sometimes though the process is of more interest. You have a number of options when booting and it s also a source of a number of problems so it pays to understand it. In this chapter we ll look at the following topics In the next section we ll look at the startup process in more detail. On page 525 we ll look at how to control the boot process. If something goes wrong and the system doesn t come up those messages that scrolled off the screen are very important. We ll look at what they mean on page 525. It s not so obvious that you need to adhere to a procedure when shutting down the system. We ll look at the hows and whys on page 537. There are a number of ways of starting the system for particular applications. On page 538 we ll look at how to run FreeBSD without a disk. v 2003 04 02 04 32 28 523 2 April 2003 17 00 47 The Complete FreeBSD . tools page 524 The Complete FreeBSD 524 Starting the system When you power up the system or when you reboot a number of actions occur before the system is up and running. Starting the system is usually called bootstrapping after the story of Baron von Munchhausen pulling himself up by his own bootstraps. The following sequence describes the sequence on the PC architecture but there are only relatively minor differences on other platforms. First the BIOS1 performs tests that check that the machine is working correctly and determines the hardware .
